LANCASTER, Texas -- A police officer and two other men, including the son of Dallas' police chief, were killed in shootings at a suburban Dallas apartment complex, authorities said.

The officer was responding to a reported domestic disturbance around 6 p.m. at the apartment complex in Lancaster, just south of Dallas, when the call was upgraded to shots fired, police spokesman Sgt. Derek Clark said. When the officer arrived, an exchange of gunfire erupted and the officer was killed.

Lancaster Police Chief Keith Humphrey identified the slain officer Monday as Craig Shaw, 37. Shaw had been an officer for five years and had two children, he said.

"We're heartbroken, and his family is devastated," Humphrey said. "(He was) one of the best people, one of the top officers in the department. Very caring, very giving, selfless, hard worker."

Shaw was the department's first officer to be fatally shot in the line of duty, he said.

The Dallas County Medical Examiner's Office identified the two other men who died as 23-year-old Jeremy McMillan and 27-year-old David Brown Jr., whose father is Dallas Police Chief David Brown.

Dallas County Sheriff's Deputy Lupe Valez says David Brown Jr. appears to have shot McMillan and then Officer Craig Shaw when he and others responded to a call of shots fired Sunday night.
The officers returned fire, and Brown was killed.

The Dallas Morning News reported that Brown, 27, was arrested on suspicion of selling marijuana in Waxahachie in 2003, but pleaded no contest and was convicted of a misdemeanor. In an interview earlier this year, Dallas Police Chief David Brown said he was proud of how his son, also a father, grew after the incident.

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